Islands:
Dominica: Columbus discovered the island of Dominica on November 3, 1493, during his second voyage.
Guadeloupe: Guadeloupe was another Caribbean island that Columbus encountered on November 4, 1493.
Montserrat: He sighted the island of Montserrat on November 11, 1493.
Antigua: Columbus discovered the island of Antigua on November 11, 1493.
Virgin Islands: Several of the Virgin Islands were discovered by Columbus, including St. Croix and St. John on November 14, 1493, and Puerto Rico on November 19, 1493.
Mainland Exploration:
Jamaica: Columbus landed in Jamaica on May 5, 1494, making it the first major island discovered by Europeans in the Caribbean Sea.
Cuba: On his second voyage, Columbus sailed along the southern coast of Cuba, exploring portions of the island.
South American Coast: Columbus explored parts of the South American mainland during his second voyage, specifically the islands of Trinidad and Tobago and the Orinoco River delta in present-day Venezuela.
It's worth noting that the exact territories and landmasses discovered by Columbus on his second voyage have variations in terminology and definitions based on historical accounts and different interpretations.